Experimental Validation of a Semi-physical Modelling Approach of the Influence of Tyre Rotation on the Vertical Tyre Force Transmission and Tyre Kinematics

Performance, development and validation of vehicle dynamics applications such as anti-lock braking systems (ABS) or indirect tyre pressure monitoring systems (iTPMS) rely on a sufficiently accurate consideration of tyre properties such as transient dynamics and tyre kinematics. Previous investigations showed that the tyre rotation has a distinct effect on the vertical tyre stiffness as well as on the three characteristic tyre radii, the unloaded, static and effective (dynamic) tyre radius. Based on the fundamentals of the TMeasy 5 handling tyre model, an enhanced semi-physical modelling approach was developed to consider rotational speed dependent tyre stiffness and tyre radii in an effective and numerically efficient manner. In the present study, a detailed experimental validation is conducted to verify, evaluate and validate the previously identified rotational speed induced effects and the developed enhanced modelling approach. Based on the results of an extensive tyre testing series, it is shown that the rotational speed induced tyre behaviour can be taken into account effectively by considering a linear dependence of the vertical tyre stiffness and a non-linear progressive one of the unloaded radius on the rotational speed. The resulting rotational speed induced behaviour of the static and effective tyre radius is approximated with sufficient accuracy by the enhanced model. With the presented semi-physical modelling approach and identified rotational speed induced tyre behaviour, applications such as ABS, iTPMS or driving simulators can be enhanced.